Mophie is the market leader for smartphone battery cases, even though its premium products are priced higher than most of the competition. If you’ve upgraded to the iPhone 7 then see our round of the best iPhone 7 battery cases. You know what you are getting with a Mophie battery case: quality design, trustworthy battery life, and solid protection. You can buy slimmer cases, but usually with some compromises. Mophie claims that its cases are the only ones manufactured in the same factories as Apple’s iPhones themselves. The company even makes its own cables to ensure quality throughout. The Mophie Juice Pack Air and Juice Pack Plus for iPhone 6, and Juice Pack for iPhone 6 Plus are all MFI certified by Apple, and triple tested for endurance, speed and durability. All of the above is why – at £89.95 for the Juice Pack Air, £109.95 for the Juice Pack Plus for iPhone 6, and £89.95 for the Juice Pack for iPhone 6 Plus – these battery cases are more expensive than the average power pack. All the Mophie cases prioritise iPhone charging first, followed by the case battery. And, unlike many cheaper battery cases, you can both charge and sync using the supplied Micro USB cable, and not have to remove the case every time you need to sync with your computer. The Juice Pack Air is the entry-level Mophie battery case for the iPhone 6. Its 2,750mAh battery capacity buys you a full recharge on a near-dead iPhone 6 – enough to keep you going till the next charging opportunity. Its bigger brother, the rather confusingly named Juice Pack Plus (that isn’t for the iPhone 6 Plus), packs a higher-capacity 3,300mAh battery. This gave us a full recharge and about an extra 20 percent again after that. The Juice Pack for iPhone 6 Plus has a smaller 2,600mAh battery, but this adds to the phone’s already capable charge power. Expect to get 60-70 percent charge on the iPhone 6 Plus. All models are available in tactile matt black, glossy white and sleeker gold colours. The Juice Pack Plus also offers greater iPhone safety than the others, with what Mophie calls its Impact-Isolation System – active-suspension bumpers inside the case for more robust shock and impact protection. As a result of this added protection and higher battery capacity it’s slightly bulkier and heavier than the Air. In fact, as the Mophie for the iPhone 6 Plus is the slimmest of them all, it shows that it’s the battery that adds girth, not the protection. The Air is pretty tough too, mind. All models feature a screen-saving raised bezel to stop cracks and scratches. Pass-through mute switch, volume and lock buttons protect the ports and switches. The Mophie cases for iPhone 6 and 6 Plus are as simple as the previous Mophie generations, with a mechanical switch on the back so you can turn on and off charging as it suits you. Four LEDs show you approximately how much charge is left in the case battery. Mophie has also stuck with the pop-off top and slider-style body design for all its battery cases. There are slimmer battery cases for the iPhone 6. We particularly like the £54.99 iWalk Chameleon i6 Power/Bumper Case, which is lighter and thinner than the Mophies. And maybe the smartest design of all iPhone 6 battery cases comes from Tylt, with its £89.99 Energi Sliding Power Case, which features a dual design where you carry the phone around in a tight, ultra-slim protective case and only add to a charging case when required. This means, of course, that you need to keep the case with you when out and about for long periods of time, but does keep the phone protected outside of the charger. Read our Best iPhone 6 battery cases round up for reviews of as many cases as we have laid our hands on. The Juice Pack Air measures 7.42cm x 15.5cm x 1.55cm (2.92in x 6.10in x 0.61in), and weighs 99g (3.5oz). The higher-capacity and more robust Juice Pack Plus measures a slightly larger 7.44cm x 15.57cm x 1.68cm (2.93in x 6.13in x 0.66in), and weighs 110g (3.9oz). The Juice Pack Plus measures 8.31cm x 17.4cm x 1.45cm (3.27in x 6.85in x 0.57in), and weighs 110g (3.9oz). Mophie is soon to launch an iPhone 6 version of its excellent Space Pack case, which offers both power and up to 128GB of storage via its Space app for iOS. As soon as we have one to test we’ll review it here. Thankfully Mophie now has its own UK store so you can order without having to calculate international shipping fees, and avoid the many counterfeit Mophies you’ll find at many online retailers. All come with Micro USB charging cable and a headphone port adapter (for users of angled or short headphone jacks). Simon was Editor of Macworld from the dark days of 1995 to the triumphant return of Steve Jobs and the launch of the iPhone. His desk is a test bench for tech accessories, from USB-C and Thunderbolt docks to chargers, batteries, Powerline adaptors and Fitbits.